1. Technical Field
The present invention relates to a minute connector having minute contact structure.
2. Description of the Related Art
The contacts of most of the current connectors are fabricated by the press piercing of a plate that uses the spring material. It is thought that the lower limit of the size of the contact is about 0.2 mm under mechanical fabrication. On the other hand, in the connection interface structure of the semiconductor equipment, the structure of 0.1 mm or less has already been realized. The connection interface of the semiconductor equipment is, however, not aimed to repeat steady detaching.
In recent years, the miniaturization of connectors has been accelerated in accordance with the miniaturization of electronics devices. Minute contacting portions with the size and the pitch being disposed of 0.2 mm or less are required in accordance with the miniaturization of the connectors. In the case of forming such contacting portions, it is difficult to precisely fabricate under machine work around the lower limit of the fabricating preciseness. Furthermore, the manufacturing yield decreases and the manufacturing cost increases.
As a method of forming a minute contacting portions, metallic pattern formation technique by electroforming method or electroplating method, or the method of forming the conductive pattern using minute conducting particles or the like are known. In the contact formed by the methods mentioned above, the oxide film will be formed on the surface and the surface becomes uneven. In order to steadily obtain the connection with a low contacting resistance, it is required to destroy the oxide film by making the contacts slide mutually under pressure and to increase the contacting area between the contacts by applying a certain load.
In a minute contact being made of the metallic pattern or the conductive pattern, however, it is difficult to secure the elasticity modulus and to obtain the steady contact between the contacts. Moreover, increasing of the pressing force to secure the contact of the contacting portions causes the problems of the minute transformation by abrasion of the surfaces of the contacts or the short-circuit by abrasion powder or the like. In this way, it is questionable to apply pressure with the load or the like to minute contacting portions.
Connectors being formed with carbon nanotubes (CNT) having excellent abrasion tolerance and high electric conductivity orienting in the direction of the thickness of a substrate and using the CNT as contacts are reported (refer to Japanese Patent Application Publication Nos. 2009-7461 and 2007-287375). In order to secure the contact of the contacting portions, the end portions of CNT bundles that are composed of a plurality of CNT's are protruded from the opening edge of the substrate. If the CNT bundles are made contacted with metal electrodes by pressing, the CNT bundles will be dispersed. In this case, because a part of CNT's is dispersed outside or buckled, there is a possibility that the contact with the adjacent contacts or the like will be caused. This might prevent the pitch from being narrowed.